题解 | #平均活跃天数和月活人数#
平均活跃天数和月活人数
https://www.nowcoder.com/practice/9e2fb674b58b4f60ac765b7a37dde1b9
select date_format(submit_time,'%Y%m') as month, round((count(distinct uid, date_format(submit_time,'%Y%m%d')))/count(distinct uid),2) avg_active_days, count(distinct uid) mau from exam_record where year(submit_time)=2021 and submit_time is not null group by date_format(submit_time,'%Y%m')
